I've recently tested an old AWS application of mine which I created more than half a year ago. I was very surprised finding out that an instance which I deleted long time ago still works. And the app extracts data from this phantom. This is very confusing. How this even possible?
As you can see on the screenshot no instances are running.
Just to double check I've used mysql workbench to test the connection settings of the app and it works.
It may have to do with ElasticBeansTalk auto-config start-up, but again it show db instances running and there are none.
Make sure you are looking at the correct region: for most of the aws services (with the exception of IAM and S3) each region is handled entirely separately.